Latch assembly of fire door lock

Abstract

A latch assembly of fire door lock comprises a latch base with a bottom, a latch bolt, a stopper, a resilient member and a linked unit. The latch bolt is retractably pivoted within the latch base and having a blocked surface. The stopper is swayingly pivoted within the latch base and having a blocked protrusion. The resilient member is disposed between the bottom of the latch base and the stopper and contacts against the stopper. The blocked protrusion of the stopper is capable of engaging with the blocked surface of the latch bolt. The linked unit is disposed within the latch base and pivotally connected with the latch bolt.

1 . A latch assembly of fire door lock comprising:
 a latch base having a bottom;   a latch bolt retractably pivoted within the latch base and having a blocked surface;   a stopper swayingly pivoted within the latch base and having a blocked protrusion;   a resilient member disposed between the bottom of the latch base and the stopper and contacting against the stopper, the blocked protrusion of the stopper is capable of engaging with the blocked surface of the latch bolt; and   a linked unit disposed within the latch base and pivotally connected with the latch bolt.   
   
   
       2 . The latch assembly of fire door lock in accordance with  claim 1 , wherein the stopper has a first surface and a second surface opposite to the first surface, the resilient member contacts against the second surface and the blocked protrusion projects from the first surface. 
   
   
       3 . The latch assembly of fire door lock in accordance with  claim 2 , wherein the latch bolt further has an arc surface adjacent to the blocked surface and the blocked protrusion of the stopper is capable of pressing the arc surface of the latch bolt. 
   
   
       4 . The latch assembly of fire door lock in accordance with  claim 3 , wherein the latch bolt further has a step portion formed at the blocked surface but adjacent to the arc surface, the blocked protrusion of the stopper is capable of engaging with the step portion. 
   
   
       5 . The latch assembly of fire door lock in accordance with  claim 2 , wherein the stopper has a first end swayingly pivoted within the latch base and a second end opposite to the first end, the blocked protrusion is formed between the first end and the second end. 
   
   
       6 . The latch assembly of fire door lock in accordance with  claim 5 , wherein the stopper has at least one fixing portion formed at the first end of the stopper. 
   
   
       7 . The latch assembly of fire door lock in accordance with  claim 6 , wherein the stopper has two fixing portions and each of the fixing portions projects from the first surface of the stopper. 
   
   
       8 . The latch assembly of fire door lock in accordance with  claim 6 , wherein the stopper has two fixing portions and each of the fixing portions projects from the second surface of the stopper. 
   
   
       9 . The latch assembly of fire door lock in accordance with  claim 5 , further comprising a fixing pin installed penetrating the fixing portion of the stopper and fixed the fixing portion at the latch base. 
   
   
       10 . The latch assembly of fire door lock in accordance with  claim 2 , wherein the resilient member has a support end contacting against the second surface of the stopper. 
   
   
       11 . The latch assembly of fire door lock in accordance with  claim 1 , wherein the bottom of the latch base has a trench, one end of the resilient member is disposed at the trench of the bottom and another end contacts against the stopper. 
   
   
       12 . The latch assembly of fire door lock in accordance with  claim 1 , wherein the resilient member has a contact end pressing at the bottom of the latch base. 
   
   
       13 . The latch assembly of fire door lock in accordance with  claim 1 , wherein the resilient member has a contact end capable of fixing at the bottom of the latch base. 
   
   
       14 . The latch assembly of fire door lock in accordance with  claim 1 , wherein the latch base further has a first lateral, a second lateral opposite to the first lateral and a space formed among the first lateral, the second lateral and the bottom. 
   
   
       15 . The latch assembly of fire door lock in accordance with  claim 14 , wherein the first and second laterals have a bias runner formed thereon respectively, the bias runners are corresponding to each other and communicate with the space. 
   
   
       16 . The latch assembly of fire door lock in accordance with  claim 15 , further comprising at least one self-locking member that is disposed into the bias runners of the first lateral and the second lateral. 
   
   
       17 . The latch assembly of fire door lock in accordance with  claim 16 , further comprising a pair of hot-melt members that are fixed at each of the bias runners of the first and second laterals respectively and block the self-locking member. 
   
   
       18 . The latch assembly of fire door lock in accordance with  claim 16 , further comprising a hot-melt member which is inserted into and fixed at each of the bias runners of the first and second laterals and blocks the self-locking member. 
   
   
       19 . The latch assembly of fire door lock in accordance with  claim 16 , wherein each of the bias runners has a position hole, the self-locking member is capable of sliding into each of the position holes and blocking the linked unit. 
   
   
       20 . The latch assembly of fire door lock in accordance with  claim 19 , wherein the linked unit at least comprises a middle rod, the self-locking member is capable of blocking the middle rod of the linked unit. 
   
   
       21 . The latch assembly of fire door lock in accordance with  claim 14 , further comprising at least one self-locking member, the linked unit at least comprising a middle rod and a lower rod, the self-locking member is pivotally disposed at one side of the middle rod. 
   
   
       22 . The latch assembly of fire door lock in accordance with  claim 21 , wherein further comprising a hot-melt member that is inserted into and fixed at the latch base, the self-locking member has a limit end contacting against the hot-melt member. 
   
   
       23 . The latch assembly of fire door lock in accordance with  claim 21 , wherein the first and second laterals have a longitudinal runner formed thereon respectively, the longitudinal runners are corresponding to each other and communicate with the space. 
   
   
       24 . The latch assembly of fire door lock in accordance with  claim 23 , further comprising a joint pin slideably disposed into the longitudinal runners of the first and second laterals and a connection rod, the joint pin connects the lower rod of the linked unit and the connection rod. 
   
   
       25 . The latch assembly of fire door lock in accordance with  claim 24 , wherein the self-locking member is capable of blocking the joint pin. 
   
   
       26 . The latch assembly of fire door lock in accordance with  claim 25 , wherein the self-locking member has a limit end capable of blocking the joint pin. 
   
   
       27 . The latch assembly of fire door lock in accordance with  claim 1 , further comprising a restoration spring which is pivotally disposed at one end of the latch bolt and one end of the restoration spring contacts against the latch bolt.